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  Topic: Creating CSI with NS, H T T H H H T H T T H H H H T T T< Next Oldest | Next Newest >  
rossum



Posts: 186
Joined: Dec. 2008

(Permalink) Posted: Nov. 20 2012,09:56   

Quote (Cubist @ Nov. 20 2012,09:15)
So if this CSI thingie genuinely is the sure-fire Design-detection tool which you ID-pushers assert it to be, it seems to me that you should be able to use it to distinguish random garbage from meaningful text that only appears to be random garbage.

That is a very significant thing to do.  The NSA/GCHQ would be very interested in a distinguisher like that, which could tell the difference between an encoded message and junk.  It defeats one of the obvious ways to block traffic analysis -- just fill up the comm link with junk when it is not being used, so it always appears to be running at the same capacity.

The first attack against a cypher is often a distinguisher, that is a way to tell the output of the cypher from true random.  One of the attacks against the RC4 keystream (due to Mantin and Shamir) showed that the second byte of the keystream was 0x00 with a frequency of 1/128 instead of the expected 1/256.  Obviously that attack only works for RC4 and not for other cyphers.  What the Discovery Institute claims to have is a general distinguisher, valid for all current and future cyphers.  Hence they are in effect claiming to have a way to attack any cypher whatsoever.

If CSI really is such a distinguisher, then the Discovery Institute is being very unpatriotic in not offering it to the NSA immediately.

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The ultimate truth is that there is no ultimate truth.

  
  128 replies since Oct. 06 2012,18:57 < Next Oldest | Next Newest >  

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